Starting time

Give input on tuning as well as any tips and tricks you may have. Also feel free to share base mapping files for various engine types.
Post Reply
gnutz2
Posts: 190
Joined: Tue Jul 03, 2012 2:33 am
ECU Model: S100 Pro

Starting time

Post by gnutz2 »

How fast does your car start? More specifically how many turns before it fires.

Mine has always took about 5-6 revolutions (which feels like for ever) of the engine before it thinks about firing, I had a feeling when I went to sequential it might fire earlier but no luck, it's really niggling me now as I know some engines that barely turn one revolution before firing (although they are higher compression than mine)

The engine is inline 5 cylinder with 8 to 1 compression, the flywheel has 15-1 reference pins for timing.

I've adjusted the after start enrichment and there seems to be a sweet spot where it likes to fire so that only leaves the ignition which is flywheel teeth before tdc (in main engine settings). This needs to be set at 0 when the engine is cold and that gives best starting, when the engine is hot this can be set at 1 and 2 for a faster start but if the engine cools it won't start and actually tries to backfire and locks the engine which is understandable when you consider one tooth is 24 crank degree's.

My only thoughts on the matter is that the engine would like somewhere in-between 0 and 24 degrees of timing for cranking but at the moment I'm limited to this flywheel.

Also would I be correct in thinking the water temp vs ignition correction would only effect the main map and have no effect on cranking??

Cheers guys.
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Starting time

Post by stevieturbo »

I only ever used 0 firing tooth.

Strictly speaking, batch would start quicker than sequential, purely because with sequential the ecu may have to wait until sync is confirmed before it will start.

Whereas with batch that doesnt matter.

5 seconds does sound like a long time though. Mine may have taken that long on occasion, but most times it started quite quickly.

Does it change if you open the throttle slightly ?

Cranking should only rely on the cranking settings, only transitioning once started. Have you tried datalogging starting ? Logging should start as soon as the crank is rotating.

Not honestly sure if that's something I ever tried or paid attention to.
gnutz2
Posts: 190
Joined: Tue Jul 03, 2012 2:33 am
ECU Model: S100 Pro

Re: Starting time

Post by gnutz2 »

Hi Stevie, its 5-6 revolutions not seconds, which seems like a couple of seconds (I'll log it and see exactly what's going on.

As I said its not a massive problem but does annoy the hell out of me.
katana
Posts: 455
Joined: Sun Jan 27, 2013 6:08 pm
ECU Model: S60 Pro
Firmware Version: 29

Re: Starting time

Post by katana »

Is your lifetime so short that you begrudge waiting 2 seconds? Even F1 cars take longer than that to fire with all their procedures - their crew must be suicidal in comparison! LOL LOL
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Starting time

Post by stevieturbo »

Yea, chill, I thought you meant 5-6 seconds

If anyone thinks it's broke, tell them it doesnt start until you have oil pressure for engine longevity reasons lol

With batch and most crank triggers, it cannot start in less than 1 turn. With sequential, in theory it shouldnt be able to start in less than 2 turns.
PhillipM
Posts: 177
Joined: Tue May 13, 2014 5:30 am
ECU Model: S80 Pro
Distributor: DTA UK
Firmware Version: 73

Re: Starting time

Post by PhillipM »

Rotary used to fire up in 2-3 revolutions.
Until the seals died, and you end up towing it around the pits for 5 minutes.
gnutz2
Posts: 190
Joined: Tue Jul 03, 2012 2:33 am
ECU Model: S100 Pro

Re: Starting time

Post by gnutz2 »

Ha ha guys, some funny responses :D

I know it's me that has the problem (impatience and OCD :| ).
Post Reply